Embedded Automobile Engine Locking System, Using GSM Technology

Transcription

1 Embedded Automobile Engine Locking System, Using GSM Technology Jayanta Kumar Pany 1 & R. N. Das Choudhury 2 1 Dept. of Electronics and Communication Engineering, Raajdhani Engineering College, BPUT, Odisha, India 2 Dept. of Electronics and Instrumentation Engineering. ITER, SOA University, Odisha, India jayanta.dpany@gmail.com 1, rndc123@yahoo.co.in 2 Abstract - This paper deals with the design & development of an embedded system, which is being used to prevent /control the theft of a vehicle. developed instrument is an embedded system based on GSM technology. instrument is installed in the engine of the vehicle. An interfacing GSM modem is also connected to the microcontroller to send the message to the owner s mobile. main objective of this instrument is to protect the vehicle from any unauthorized access, through entering a protected password and intimate the status of the same vehicle to the authorize person (owner) using Global System for Mobile (GSM) communication technology. This system deals with the concept of network security. main concept in this design is introducing the mobile communications into the embedded system. entire designed unit is on a single board. Keywords - Pass Word, GSM Modem, AT Commands, Interfacing, I 2 C, RS232 and UART protocols. I. INTRODUCTION In these days, automobile thefts are increasing at an alarming rate all over the world. So to escape from these thieves most of the vehicle owners have started using the theft control systems. commercially available anti-theft vehicular systems are very expensive. Here, we make an attempt to develop an instrument based on 8051 microcontroller and operated using GSM technology. instrument is a simple and low cost vehicle theft control embedded system. Global System for Mobile communications (GSM) is the most popular and accepted standard for mobile phones in the world established in 1982 and it operates in 900 MHz frequency. Over billion people use GSM service across the world. utility of the GSM standard makes international roaming very common between mobile phone operators, enabling subscribers to use their phones in many parts of the world. GSM differs significantly from its predecessors in both signaling and speech clarity, as its channels is digitized. It means that the GSM system is now considered as a third generation (3G) mobile communication system. II. COMPONENTS, INTERFACINGS AND PROTOCOLS: 1. AT89S52 Microcontroller 2. DC Power supply unit 3. 4x3 Matrix keypad 4. 16x2 Liquid crystal display (LCD) 5. 12V Relay and DC Fan 6. GSM Modem 7. GSM Mobile 8. MAX232 line driver 9. 24C02 E 2 PROM 10. L293D motor driver & DC motor 11. Buzzer 12. DB9 connector 2.1 Microcontroller Unit: AT89S52 is a low-power, high-performance complementary metal-oxide semiconductor (CMOS) 8- bit microcontroller with 8K bytes of flash programmable and erasable read only memory (FPEROM). device is manufactured using Atmel s high-density nonvolatile memory technology and is compatible with the industry standard 80C51 and 80C52 instruction set and pin out. on-chip flash allows the program memory to be reprogrammed in-system or by a conventional nonvolatile memory programmer. By combining a versatile 8-bit central processing unit (CPU) with flash on a monolithic chip, the Atmel AT89S52 is a powerful microcontroller, which provides a highly flexible and 49

2 cost effectivee solution to applications. many embedded control Fig. 01 : Block Diagram Features of the microcontroller: 1. It is a 8-bit microcontroller with KHz. of machine cycle 2. It has got a external crystal oscillator with MHz frequency 3. 8K bytes of flash ROM and 256 bytes of RAM 4. 4 bidirectional I/O ports with 8 pins each 5. Threee 16-bit timer/counters with 4 modes of operation. 6. A six-vector two-level interrupt architecture 7. A full duplex serial port(uart) with 28.8KHz frequency 8. 8-bit data bus and 16 bit address bus 2.2 DC Power Supply Unit: DC power supply unit is divided into 4 elements as below V/12V step down Transformer. 2. Bridge Rectifier with 4 x 1N4007 diodes µ F/35V Capacitor as a Filter Voltage Regulator IC. Fig. 02 : Circuit Diagram of Power Supply This transformer steps down the incoming line voltage depending on the needs of the power supply. This alternating voltage is then fed to the rectifier. rectifier is a diode circuit that converts the ac to pulsating dc. This pulsating dc is then applied to the filter circuit. filter is a circuit that reduces the variations of the dc voltage. Here the capacitor is used as a filter. filtered dc is then fed to a voltage regulator stage. voltage regulator is used to maintainn a constant voltage at the power supply output. It also provides a further smoothing of the dc voltage. We are using an IC 7805 as voltage regulator to get a 5V outpu voltage X3 Matrix Keypad: Keypads and LCDs are the most widely used input/output devices. In this section, we first discuss keypad fundamentals, along with key press and key detection mechanisms, and then it is shown how a keypad is interfaced to an 8051 µc. Keypads are organized in a matrix of rows and columns. CPU accessess both rows and columns through ports. When a key is pressed, the row and column are connected; otherwise there is no connection between them. Scanning and identifying the key pressed: Fig. 03 : Schematic diagram of Keypad 50

3 In the above figure a 4X3 matrix keypad is connected between two ports. rows are connected to an output port and the columns are connected to an Input port. If no key has been pressed, reading the input port will yield 1s for all columns since they are alll connected to high voltage (Vcc). If all the rows are grounded and a key is pressed, one of the columns will have 0 since the key which is pressed provides the path to ground. It is the function of the microcontroller to scan the keyboard continuously to detect and identify the key which has been pressed. 2.4 Liquid Crystal Display (LCD) unit: A 16x2 character Line LCD module is a parallel port module. An 8051 program must interact with the outside world using input and output devices that communicate directly with a human being. One of the most common devices attached to an 8051 µc is an LCD display. LCD requires 3 control lines as well as 8 I/O lines for the data bus. So this LCD will require a total of 11 dataa lines. Fig. 04 : Schematic diagram of LCD threee control lines are referred to as EN, RS, and RW. EN line is called "Enable."" This control line is used to tell the LCD that you are sending it data. enable pin used by the LCD latches the information presented to its data pins. When data is supplied to data pins, high to low pulse must be applied to this EN pin in order to latch the data present at the data pins. This pulse must be a minimum of 450 ns wide. RS line is the "Register Select" line. When RS is low (0), the data is to be treated as a command or special instruction (such as clear screen, position cursor, etc.). When RS is high (1), the data being sent is text data, which should be displayed on the screen. RW line is the "Read/Write" control line. When RW is low (0), the information on the data bus is being written to the LCD. When RW is high (1), the program is effectively querying (or reading) the LCD. Some commands are given below for reference. Code (Hex) C0 Table 01: LCD Command Codes Command to LCD Instruction Register Clear Display of the screen 2 line, 5X7 Matrix Force cursor to begin from 1 st line Force cursor to begin from 2 nd line V Relay and DC Fan: relay is an electromagnetic switch. When relay is activated, then it closes the loop of ignition, hence start the engine. When relay is de-activated, it opens the loop of ignition, hence stop the ignition of the automobile. A DC Fan is connected with the relay replicating the automobile engine to verify the operation of the system. 2.6 GSM Modem: GSM/GPRS Modem comes with a serial interfacee through which the modemm can be controlled using AT command interface. Heree a SIMCOM made (SIM300) modem interfaced with the microcontroller operates in 900 MHz frequency. protocol used by GSM modems for setup and control is based on the AT-Command set. GSM modem specific commands are adapted to the services offered by a GSM modem such as: text messaging, calling a given Phone number, deleting memory locations etc. Since the main objective for this application is to show how to send and receivee text messages, only a subset of the AT-Command set needs to be implemented. following section describes the AT-Command set. Table 02: AT Command Sets Command AT ATE0 AT+CNMI AT+CPMS AT+CMGF AT+CMGR AT+CMGS AT+CMGD 2.7 GSM Mobile: Description Check if serial interface and GSM modem is working. Turn echo off, less traffic on serial line. Display of new incoming SMS. Selection of SMS memory. SMS string format, how they are compressed. Read new message from a given memory location. Send message to a given recipient. Delete message In our project we used a GSM mobile to receive the SMS sent by the instrument regarding the engine-on status. mobile number must be programmed with the source code. So that the control unit can send the SMS and in the same time the authorized person received the same SMSS to take care of his vehicle. 51

4 2.8 MAX232 line driver: A MAX232 chip is required to convert RS232 voltage levels to TTL levels, and vice versa has one transmitter (TxD) and a receiverr (RxD) for transferring and receiving serial data from the port 3 (P3.0 and P3.1).y requiree a line driver to make them RS232 compatible. A line driver converts the R232 s signals to TTL voltage levels that will be acceptable to 8051 s TxD and RxD pins. 2.9 AT24C022 E 2 PROM: AT24C02 is a 256 byte/ 2K-bit EEPROM, which used to retain the password even after power failure. device is organized as a single block of 256 x 8-bit memory with a two-wired serial interface. 24C02 supports a bi-directional two-wired bus and data transmission [I 2 C] protocol. bus has to be controlled by a master device (µc) which generates the serial clock (SCL), controls the bus access, and generates the START and STOP conditions, while the 24C02SC works as slave L293D motor driver IC & DC motor: purpose of using 4 no. of 12V DC motors is to drive the hardware kit just like an automobile. Since, MCU can interpret the logic 1as 5v & 0 as 0v, so L293D motor driver IC is used to convert 5v logic to 12v logic to drive the motor efficiently with full RPM. Here used one IC to drive 2 motors. Accordingly there are used two ICs for our prototype model Buzzer A buzzer is an audio signaling device, which may be mechanical, electro-mechanical or electronic. Typical use of buzzers / beepers includes alarms and timers etc. III. ASSEMBLY OF THE SYSTEM: All electronic components are assembled on a single Vero-board. After mounting and soldering of the components and sockets as shown in the photograph, the other peripherals like keypad, LCD, Buzzer, microcontroller with other ICs are mounted/ inserted. For power supply unit a 230V AC followed by a step down transformer and a full wave bridge rectifier circuit is used as shown in the circuit diagram. Alternatively a 12V DC supply from a 12V battery is use for circuit operation. Now, output power supply is given 5v to MCU & 12v to Relay. Relay connected to pin-0 of port-0 of the MCU. Keypad connected from pin 0 to 3 row wise and from pin 4 to 6 of port-1 column wise. GSM modem connected to pin 0&1of port-3. Again LCD is connected to the pin 0 to 7 of port -2 and pin 2 to pin 4 of port -0 as shown in the circuit diagram. A 12V dc Fan is connected with the relay replicating the automobile engine. That means when the relay is activated the fan will move. Otherwise it will be idle. L293D IC-1is interfaced with port 0-5&6 and port 3-3 &4, where as L293D IC-2 is connected to port 0-1 &7 and port3-2 & port1-7 as shown in the circuit diagram. IV. INTERFACINGS AND PROTOCOLS USED: In this project there are six interfacings used like 4x3 Matrix Keyboard, 16x2 LCD, GSM Modem, Motor Driver IC L293D, 12v Relay, 12v Buzzer etc. In addition, three protocols are being used like RS232, I 2 C, UART to functional the instrument successfully. Circuit Diagram: Fig. 05: Complete Circuit Board Fig. 06: Circuit Diagram V. WORKING OF THE MODULE: embedded system installed in the engine of the vehicle along with the GSM modem. By entering a correct password(like: *abcd) the instrument allows to activate the 12V relay and then ignition of the engine will start. Hence start the vehicle.if anyone tries to enter the password randomly, then after three trials, the MCU will block the entry of further password. n, the buzzer will turned on to create a noise to panic the 52

5 culprit, followed by sending a message Alert: Car Is Under Threat through GSM modem to the owner s mobile for further action for prevention of his vehicle. According to the prototype model after entering correct password the Fan will move and at the same time, according to the instruction it will run forward for 10 sec and backward for10 sec like an automobile. Password can be changed by the following proper procedure. First enter #, then enter the old password, then new password. Now test, whether the new password is working or not. As per algorithm given below the new password will retain even after power failure. So it will work as usual. source code is written in embedded C language. To develop the source code the flow chart of the project is shown in the figure below. VI. CONCLUSION: This is a unique method of designing and assembling a low-cost, compact theft control system for an automobile. This instrument is an ultimate threat to vehicle thieves. By installing this instrument in the automobile engine it is very difficult to access by an unknown person, since it is based on GSM Technology. In future, there is no doubt, that all of the vehicles will be embedded with this unique kit. In addition to the above features we can also add extra features like thumb/face recognition to ascertain more security of the vehicle. REFERENCE: [1] B.G. Nagaraja, Ravi Rayappa, M. Mahesh, Chandrasekhar M. Patil, Dr. T.C. Manjunath:- Design & Development of a GSM Based Vehicle ft Control System / IEEE, DOI /ICACC , pp [2] M. A. Mazidi, 8051 Microcontroller & Embedded Systems, Pearson Education Asia, India, 2 nd edition, [3] Kenneth J. Ayala, 8051 micro-controller Architecture, programming & applications, Penram International, India, [4] Raj Kamal, Embedded System- Architecture, Programming and Design, Tata McGraw Hill Publisher, 2 nd edition, [5] Myke Predco, Programming and customizing 8051 microcontroller, Tata McGraw Hill Publiser. [6] Toshiba's 1993 NAND Flash Applications Design Guide. [7] Millman & Grable, "Combinatorial Digital Circuits" and "Sequential Digital Circuits" of, Microelectronics, 2nd edition. [8] National motor vehicle theft reduction conference 2000, Conference Papers (Australia). [9] Stolen and Wrecked Vehicles Monitoring Program, CCMTA June 1994 (Canada). [10] CCMTA Best Practice Models for Combating Auto ft, Version 6.1, Oct. 2006, Anti Auto- ft Project Group. [11] [12] [13] [14] [15] microcontroller [16] 53